COMMISSION 27 OF THE I. A. U. INFORMATION BULLETIN ON VARIABLE STARS NUMBER 792 Konkoly Observatory Budapest 1973 May 22 FIRST EPHEMERIDES OF FIVE VARIABLE STARS IN ERIDANUS AND FORNAX The variable stars discussed in the present paper were discovered by Mrs De Lannoy on plates taken with the 10" Metcalf telescope of the Boyden Observatory. Charts on which the variables and their comparison stars have been marked are given in Figure 1. They represent a field of approximately 30'x 30' around each variable. North is always at the top. Variable 4 is identical with BT Eridani (CPD -39d 325), no chart is given. Table 1 gives a synopsis of our investigation. The brightnesses of the comparison stars are given in Table 2. They are derived from star-counts, made in a field of 1/4 square deg. around each variable, and compared with the tables in Groningen Publication no. 43. The brightness of the comparison stars for the variable BT Eridani, however, was taken from the Cape Photographic Durchmusterung. Details of the least-squares solutions, performed by an electronic computer of the Computing Centre at the University of Louvain, following a program established by Messrs. Goossens and Vissenberg, have been collected in Table 3. Data about the normal points of the mean light-curves are to be found in Table 4. Phase have always been computed with the formula phase = P^-1 (J.D.Hel. - 2436000). The normal points of the light curves are moreover represented graphically in the diagrams 1 to 5. R. DEURINCK and M. GOOSSENS Astronomisch Instituut Katholieke Universiteit Leuven Naamsestraat 61 B 3000 LEUVEN (Belgium) [FIGURE 1] [FIGURE 2] TABLE 1 --------------------------------------------------------------------------------------- Epoch m.e. phase n Brightness n R.A.(1875) Dec.(1875) Type Period m.e. J.D. of of of of 2438... single epoch ep. max. min. estim. * epoch --------------------------------------------------------------------------------------- 1 3h16m42.4s -36d12.4' RR 0.4712517d+-17 401.566d+-.012d .143p 14 14.10m 15.47m 207 2 3 29 21.8 -40 02.9 RR 0.3932027 +-54 401.261 +-.021 .929 11 14.76 15.27 175 3 3 31 51.9 -31 40.3 RR 0.4077471 +-14 401.462 +-.014 .587 23 13.28 14.95 240 4 3 32 09.4 -39 47.8 RR 2.112299 +-64 400.741 +-.061 .553 7 8.48 9.22 235 5 3 37 42.8 -32 07.9 RR 0.4791230 +-25 401.279 +-.018 .821 15 13.59 15.05 230 --------------------------------------------------------------------------------------- TABLE 2 Comparison Stars ---------------------------------------------------------------------- Var.1 Var.2 Var.3 Var.4 Var.5 * * * * C.P.D. No. ---------------------------------------------------------------------- a 13m71 a 14.37m a 12.61m a -40d 330 8.2m a' 13.14m b 14.20 b 14.78 b 13.57 b -39d 321 8.6 a 13.57 c 14.89 c 15.05 c 14.40 c -39d 320 9.5 b 13.75 d 15.41 d 15.32 d 14.69 c 13.88 e 15.52 e 14.94 d 14.46 e 14.50 f 14.69 g 15.17 ---------------------------------------------------------------------- TABLE 3 ------------------------------- ------------------------------ J.D. max. t O-C J.D. max. t O-C ------------------------------- ------------------------------ Var 1 Var 3 (cont) 2437 2437 223.4248 0 -0.0119 688.2993 1145 -0.0133 255.4618 68 -0.0201 2438 261.6066 2551 +0.0016 291.3037 144 +0.0068 263.6400 2556 -0.0038 634.3628 872 -0.0054 268.5446 2568 +0.0079 635.3146 874 +0.0039 760.2849 3774 +0.0061 668.3157 944 +0.0174 995.5790 4351 +0.0290 693.2827 997 +0.0081 2439 006.5440 4378 -0.0153 2438 261.5961 2203 -0.0082 055.4627 4498 -0.0259 262.5680 2205 +0.0212 066.5098 4525 +0.0106 2439 056.5948 3890 -0.0122 089.3405 4581 +0.0092 066.4980 3911 -0.0030 093.4289 4591 +0.0198 094.3118 3970 +0.0061 798.3951 6320 -0.0092 118.3399 4021 +0.0000 2440 178.4116 7252 -0.0137 2440 124.4589 6156 -0.0030 ------------------------------- ------------------------------ Var 2 Var 4 2437 142.5991 0 -0.0202 2437 604.4582 0 +0.0538 291.2928 378 +0.0429 2438 265.6095 313 +0.0555 267.5819 314 -0.0843 577.4887 1106 -0.0127 2439 055.5013 687 -0.0519 588.5107 1134 -0.0004 089.3405 703 -0.0091 605.4338 1177 +0.0150 091.4477 704 -0.0153 633.3465 1248 +0.0103 2440 143.4392 1202 +0.0519 688.3479 1388 -0.0367 ------------------------------ 2438 263.6399 2851 -0.0003 265.5991 2856 -0.0071 267.5716 2861 -0.0007 798.4058 4211 +0.0107 Var 5 ------------------------------- 2437 142.5989 0 -0.0237 286.3489 300 -0.0106 Var 3 581.4966 916 -0.0026 604.5032 964 +0.0061 2437 221.4580 0 +0.0159 605.4543 966 -0.0011 632.2932 1022 +0.0070 234.5025 32 +0.0125 689.2857 1141 -0.0162 252.4145 76 -0.0164 691.2707 1145 +0.0523 254.4600 81 -0.0096 2438 267.5923 2348 -0.0111 281.3675 147 -0.0134 268.5654 2350 -0.0038 581.4966 883 +0.0138 2439 051.4543 3984 +0.0061 588.4249 900 +0.0104 088.3329 4061 -0.0091 603.4807 937 -0.0205 468.2991 4854 +0.0137 635.3039 1015 -0.0016 798.3950 5543 -0.0061 668.3372 1096 +0.0043 821.3887 5591 -0.0107 ------------------------------- ------------------------------ TABLE 4 ---------------------------------------------------------------- ------------------ --------------------- ------------------ n phase m n phase m n phase m ------------------ --------------------- ------------------ Var 1 Var 2(cont) Var 4(cont) 5 .021 15.29 5 .952 14.79 5 .481 8.50 5 .058 15.00 5 .972 14.85 5 .501 8.82 5 .091 14.30 5 .991 14.89 5 .542 9.15 5 .112 14.10 --------------------- 5 .561 9.22 5 .137 14.19 Var 3 5 .580 8.89 5 .153 14.13 5 .597 8.87 5 .176 14.25 10 .011 14.61 10 .616 8.50 5 .187 14.30 10 .046 14.72 5 .640 8.48 5 .212 14.40 10 .098 14.76 5 .656 8.50 5 .237 14.52 10 .146 14.79 5 .684 8.49 5 .261 14.53 10 .190 14.82 5 .704 8.48 5 .289 14.48 10 .227 14.95 10 .727 8.50 10 .343 14.87 10 .269 14.85 10 .755 8.49 10 .417 15.13 10 .322 14.83 10 .799 8.49 10 .484 15.14 10 .364 14.84 10 .840 8.47 10 .538 15.23 10 .421 14.77 10 .915 8.50 10 .580 15.39 10 .492 14.24 10 .970 8.50 10 .612 15.43 5 .507 13.99 5 .992 8.49 10 .647 15.43 5 .530 13.44 ------------------ 10 .689 15.48 5 .546 13.27 Var 5 10 .729 15.47 5 .562 13.27 10 .765 15.45 5 .580 13.29 5 .018 14.41 10 .814 15.41 5 .590 13.27 5 .039 14.47 10 .853 15.43 5 .606 13.23 5 .072 4.51 10 .887 15.45 5 .635 13.50 5 .103 14.72 10 .923 15.47 5 .646 13.55 5 .114 14.76 7 .957 15.45 5 .661 13.79 5 .126 14.75 ------------------ 5 .685 14.03 5 .146 14.78 Var 2 5 .693 14.20 5 .160 14.89 5 .708 14.10 10 .180 14.85 5 .021 14.90 10 .743 14.10 10 .212 14.95 5 .057 14.98 10 .775 14.13 10 .246 14.90 5 .083 14.97 10 .809 14.32 10 .280 14.96 5 .116 15.13 10 .858 14.44 10 .320 15.01 5 .143 15.03 10 .908 14.53 10 .352 15.03 10 .183 15.07 10 .957 14.64 10 .384 15.05 10 .231 15.14 5 .975 14.74 10 .420 15.03 10 .277 15.16 --------------------- 10 .449 15.05 10 .328 15.23 Var 4 10 .486 15.00 10 .382 15.23 10 .540 15.00 10 .423 15.26 10 .017 8.50 10 .602 15.02 10 .500 15.27 10 .045 8.50 10 .660 14.93 10 .596 15.27 10 .077 8.50 10 .711 14.90 10 .665 15.23 10 .103 8.50 5 .760 13.88 10 .745 15.19 10 .166 8.50 5 .784 13.69 10 .822 15.04 10 .209 8.50 5 .807 13.59 5 .857 14.91 10 .246 8.50 5 .826 13.60 5 .887 14.86 10 .299 8.49 5 .854 13.69 5 .900 14.83 10 .341 8.49 5 .885 13.75 5 .909 14.82 10 .379 8.48 10 .934 13.94 5 .933 14.76 10 .428 8.51 10 .969 14.32 ------------------ --------------------- ------------------ ----------------------------------------------------------------